[Le Fort I surgery, sagittal osteotomy and genioplasty and their impact on the temporomandibular joint].

Dentofacial deformities of the jaws, teeth and middle and lower thirds of the face affect both function and appearance. Epidemiological studies show that many Americans suffer from a malocclusion, which alters the proportions of the face. Moreover, in about 5 per cent of cases, the deformity is great enough to cause a severe handicap. A number of years ago, only orthodontic therapy was available, its aim being to achieve an acceptable occlusal relation while improving appearance as much as possible. However, this therapy provided limited improvement. Consequently, serious cases were later treated surgically. Since the 1970s, new surgical techniques have made it possible to reposition the jaws or dentoalveolar segments. As a result, today many more cases are treated in collaboration with orthodontists and surgeons. This article summarizes the main orthognathic surgical techniques, their procedures and their effects on temporomandibular disorders.